JAJSK12C September   2020  – December 2021 TPS542A50

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Enable and Adjustable Undervoltage Lockout
      2. 7.3.2  Input and VREG Undervoltage Lockout Protection
      3. 7.3.3  Voltage Reference and Setting the Output Voltage
      4. 7.3.4  Remote Sense Function
      5. 7.3.5  Switching Frequency
      6. 7.3.6  Voltage Control Mode Internal Compensation
      7. 7.3.7  Soft Start and Prebiased Output Start-up
      8. 7.3.8  Power Good
      9. 7.3.9  Overvoltage and Undervoltage Protection
      10. 7.3.10 Overcurrent Protection
      11. 7.3.11 High-Side FET Throttling
      12. 7.3.12 Overtemperature Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Pulse-Frequency Modulation Eco-mode Light Load Operation
      2. 7.4.2 Forced Continuous-Conduction Mode
      3. 7.4.3 Soft Start
    5. 7.5 Programming
      1. 7.5.1 I2C Address Selection
      2. 7.5.2 Powering Device Into Programming Mode
      3. 7.5.3 Device Configuration
      4. 7.5.4 Output Voltage Adjustment
    6. 7.6 Pin-Strap Programming
    7. 7.7 Register Maps
      1. 7.7.1 ID Register (Offset = 0x0) [reset = 0x21]
      2. 7.7.2 STATUS Register (Offset = 0x1) [reset = 0x0]
      3. 7.7.3 VOUT_ADJ1 Register (Offset = 0x2) [reset = 0x0]
      4. 7.7.4 VOUT_ADJ2 Register (Offset = 0x3) [reset = 0x0]
      5. 7.7.5 CONFIG1 Register (Offset = 0x4) [reset = 0x0B]
      6. 7.7.6 CONFIG2 Register (Offset = 0x5) [reset = 0x2D]
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Full Analog Configuration
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2  Output Voltage Calculation
          3. 8.2.1.2.3  Switching Frequency Selection
          4. 8.2.1.2.4  Inductor Selection
          5. 8.2.1.2.5  Input Capacitor Selection
          6. 8.2.1.2.6  Bootstrap Capacitor Selection
          7. 8.2.1.2.7  R-C Snubber and VIN Pin High-Frequency Bypass
          8. 8.2.1.2.8  Output Capacitor Selection
          9. 8.2.1.2.9  Response to a Load Transient
          10. 8.2.1.2.10 Pin-Strap Setting
        3. 8.2.1.3 Application Curves
        4. 8.2.1.4 Typical Application Circuits
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Fusion Digital Power™ Designer Tool
        2. 11.1.1.2 Custom Design With WEBENCH® Tools
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 サポート・リソース
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

7.3.1 Enable and Adjustable Undervoltage Lockout

The EN pin provides electrical on/off control of the device. Once the EN pin voltage exceeds the threshold voltage (typically 1.2 V), the device starts operation. If the EN pin voltage is pulled below the threshold voltage, the regulator stops switching and enters low power shutdown.

The EN pin has an internal pullup current source, allowing the user to float the EN pin for enabling the device. The EN pin can also be externally driven high or low. When the pulse-width is less than 22us, the EN pin will detect the pulse as a low and cause the device to enter hiccup-mode. If the pulse-width is greater than 22us, then the EN pin will detect the pulse as low but will not enter hiccup-mode.

For adjustable input undervoltage lockout (UVLO), connect the EN pin to the middle point of an external resistor divider. Once the EN pin voltage exceeds the threshold, an additional 5 µA of hystersis current is added to facilitate UVLO hysteresis. Equation 1 shows the calculation of resistor divider network.

GUID-691E7344-B488-449E-82F6-7B6500A6C950-low.gifFigure 7-1 EN UVLO
Equation 1. GUID-3D5D5097-5E38-481E-B879-8BEDFDBC0093-low.gif